Loud Screeching sound

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Noquacks
Posts: 38
Joined: Thu Jun 29, 2017 2:18 pm

Loud Screeching sound

Post by Noquacks »

People,

1987 Sunbird, when I switch on the ac button to activate compressor there is immediately a loud screeching sound from the comp area. It stops after about 7-8 seconds. Vents put out ice cold ac. Then, every about 5 minutes the sound comes back, then again, goes away. Could it be the loose ac belt needing tightening? Maybe low on compressor oil?

Thanks, people.
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Cusser
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Re: Loud Screeching sound

Post by Cusser »

Noquacks wrote: Fri Oct 02, 2026 5:10 am Could it be the loose ac belt needing tightening?
That should be easy enough to check.

I might pull the belt, and check any tensioners and AC clutch pulley bearings for drag or noise. And maybe install a brand new belt.
Noquacks
Posts: 38
Joined: Thu Jun 29, 2017 2:18 pm

Re: Loud Screeching sound

Post by Noquacks »

Cusser wrote: Fri Oct 02, 2026 5:51 am
Noquacks wrote: Fri Oct 02, 2026 5:10 am Could it be the loose ac belt needing tightening?
That should be easy enough to check.

I might pull the belt, and check any tensioners and AC clutch pulley bearings for drag or noise. And maybe install a brand new belt.
Thanks, Cusser. Good tips. Will try those checks this weekend!
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